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Can no longer receive emails via Thunderbird.

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I cannot send emails from Thunderbird. I am using MS Windows 10 and my ISP is comcast.net. My email provider uses MS’s Outlook servers. For years I had no trouble using Thunderbird. Even after my email provider switched to using Microsoft’s Outlook servers. But when I subscribed to Microsoft’s Office365 and accidentally opened its Outlook module/application I was no longer able to send out emails. I could of course receive and send emails when I logged into the web version of Outlook, but while I could still receive emails I could no longer send them via Thunderbird. When I installed the latest version of Thunderbird (78.14.0 (32-bit)) I was no longer able to even receive emails. However, when I set up a “new” account (and used the email provider given password, which works at the web version of Outlook) and switched from POP3 to IMAP I was able to receive emails again, but I am still unable to send emails. I have tried numerous settings for my Outgoing Server (SMTP). None have worked. So my questions are: 1. What are the appropriate SMTP settings? I’ve tried so many, so I’m not providing the current ones. I’d like to start with a clean slate! 2. Are there any settings elsewhere that I need to tweak? 3. Why can’t I see (and alter if necessary) my password in my settings? (I assume they are still the appropriate ones that I inserted when I set up my account again.) However, even when I manually insert them after an error message and a form asking for my password they do not work. I’ve tried it with my antivirus and firewall protections (Webroot & Windows) turned off. SC

I cannot send emails from Thunderbird. I am using MS Windows 10 and my ISP is comcast.net. My email provider uses MS’s Outlook servers. For years I had no trouble using Thunderbird. Even after my email provider switched to using Microsoft’s Outlook servers. But when I subscribed to Microsoft’s Office365 and accidentally opened its Outlook module/application I was no longer able to send out emails. I could of course receive and send emails when I logged into the web version of Outlook, but while I could still receive emails I could no longer send them via Thunderbird. When I installed the latest version of Thunderbird (78.14.0 (32-bit)) I was no longer able to even receive emails. However, when I set up a “new” account (and used the email provider given password, which works at the web version of Outlook) and switched from POP3 to IMAP I was able to receive emails again, but I am still unable to send emails. I have tried numerous settings for my Outgoing Server (SMTP). None have worked. So my questions are: 1. What are the appropriate SMTP settings? I’ve tried so many, so I’m not providing the current ones. I’d like to start with a clean slate! 2. Are there any settings elsewhere that I need to tweak? 3. Why can’t I see (and alter if necessary) my password in my settings? (I assume they are still the appropriate ones that I inserted when I set up my account again.) However, even when I manually insert them after an error message and a form asking for my password they do not work. I’ve tried it with my antivirus and firewall protections (Webroot & Windows) turned off. SC

All Replies (1)

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I am using Office 365 as well, Saturday (when the 91.9.1 update was installed) I stopped receiving emails. Playing with the settings, I am able to receive again (changed from legacy settings of secureserver.net to officer365.com) but SMTP still won't connect and tells me the same (Login to server smtp.office365.com with username ***@****.*** failed